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Abstract Earth's magnetotail is filled with solar wind and ionospheric electrons, whose initial energies are significantly lower than the typical energies (temperatures) of plasmasheet electrons. One of the most common mechanisms responsible for heating of solar wind and ionospheric electrons in Earth's magnetotail is adiabatic heating caused by earthward convection of these electrons from the deep tail (i.e., from the region of a weak magnetic field) toward the region of stronger magnetic fields closer to Earth. This heating is moderated by electron losses into the ionosphere due to local wave scattering. In this study, we compare electron spectra from simultaneous observations of The Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft at different radial distances with spectra obtained from a simple model that includes adiabatic heating and losses. Our comparison shows that the model heating significantly overestimates the increase in energetic ( keV) electron fluxes, indicating that losses are essential for accurate modeling of the observed spectra. The required electron losses are similar to or even greater than the losses in the strong diffusion limit (when the loss cone is full). The latter can be interpreted as loss cone widening by field‐aligned electron acceleration.
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Bending the Curve: Molecular Manifestations of Electron Antisymmetry
Abstract As very light fermions, electrons are governed by antisymmetric wave functions that lead to exchange integrals in the evaluation of the energy. Here we use the localized representation of orbitals to decompose the electronic energy in a fashion that isolates the enigmatic exchange contributions and characterizes their distinctive control over electron distributions. The key to this completely general analysis is considering the electrons in groups of three, drawing attention to the curvatures of pair potentials, rather than just their amplitudes and slopes. We show that a positive curvature at short distances is essential for the mutual distancing of electrons and a negative curvature at longer distances is essential to account for the influence of lone pairs on bond torsion. Neither curvature is available in the absence of the exchange contributions. Thus, although exchange energies are much shorter range than Coulomb energies, their influence on molecular geometry is profound and readily understood.
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- Award ID(s):
- 1855923
- PAR ID:
- 10364579
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemistryOpen
- Volume:
- 10
- Issue:
- 12
- ISSN:
- 2191-1363
- Format(s):
- Medium: X Size: p. 1197-1201
- Size(s):
- p. 1197-1201
- Sponsoring Org:
- National Science Foundation
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